Category: Pulp & Paper Objective Questions

Pulp and Paper Multiple Choice Questions on “The Heatbox”.

1. The inlet to the heatbox must confirm an odd fiber slurry consistency and pressure across the width of the heatbox to confirm cross direction non-uniformity of paper.
a) True
b) False
Answer: b
Clarification: The inlet to the heatbox must confirm an even fiber slurry consistency and pressure across the width of the heatbox to confirm cross direction uniformity of paper.

2. An even pressure around the heatbox’s maintained by controlling the rate of recirculation.
a) True
b) False
Answer: a
Clarification: By inc. the recirculation, i.e., by reducing the pressure at the narrow end of the tapered inlet, the pressure and, therefore, flow rate at the heatbox over the narrow part of the tapered inlet is decreasing.

3. The _________ is a pressurized device that releases a uniform pulp slurry on the wire through the slice.
a) Aluminator
b) Heat gear
c) Head gear
d) Heatbox
Answer: d
Clarification: The heatbox is a pressurized device that releases a uniform pulp slurry on the wire, throughout the slice, at nearly the identical velocity as that of the wire. Original heatboxes were open, un-pressurized, and utilized a hydrostatic head for the necessary pressure.

4. A _________ could be utilized part of the way down the table to give a top coat of best quality fiber relative to the rest of the sheet.
a) Primary heatbox
b) Secondary heatbox
c) Tertiary heatbox
d) Quaternary heatbox
Answer: b
Clarification: A secondary heatbox could be used as part of the way down the table to release a top coat of best quality fiber relative to the rest of the sheet. To produce a white printing surface upon linerboard or to put secondary fiber in the middle section layer of linerboard, where contaminants such as polymers and wax hide.

5. Paper machines functioning above 2500 ft/min use a special, high pressure heatbox called as _________
a) Hydraulic heatbox
b) Mechanical heatbox
c) Chemical heatbox
d) Secondary heatbox
Answer: a
Clarification: High pressure heatbox called as a hydraulic heatbox. These heatboxes don’t use rectifier rolls because the high turbulence that’s generated with these rolls causes formation problems beyond the heatbox.

6. The _________ is a rectangular space in the heatbox where the pulp slurry is applied to the wire.
a) Slit
b) Slice
c) Gap
d) Slope
Answer: b
Clarification: The slice is a rectangular space in the heatbox where the pulp slurry is applied to the wire. It consists of a lower, fixed apron and an upper, adjustable lip controlling the slice height.

7. The slice height’s variable across the width of the _________ to confirm uniformity of the paper across the width of the paper machine.
a) Heatbox
b) Aluminator
c) Heat box
d) Paper machine
Answer: d
Clarification: Paper machines now utilized velocity formation where the lower apron protrudes out of the heatbox to direct the slice outward. The slice height is variable across the width of the paper machine to confirm uniformity of the paper across the width of the paper machine.

8. The energy of the jet’s utilized to displace the air with the return fabric into the _________
a) Fans
b) Turbine
c) Pans
d) Motor
Answer: c
Clarification: Accompanying the return fabric into the pans. As speeds inc. the energy of this air film inc. so the angle cannot be reduced. Therefore, the forming force inc. with advancing speed.

9. The eq., F = h sin (jS), for the forming force shows that the force will _________ with the speed unless the approach angle can be reduced then the sheet is “welded” to the wire.
a) Increase
b) Decrease
c) Multiply
d) Divide
Answer: a
Clarification: The eq. , F = h sin (j S), for the forming force shows that the force will increment with the speed. If the forming pressure reaches 34 kPa then the sheet’s “welded” to the wire, and never be removed. When beta = 8 degrees, this will occur at a speed of 4500 ft/min.

10. With _________ formation, the upper lip comes out beyond the apron and the jet’s directed toward the wire, which may cause poor formation, poor retention, and wire mark.
a) Bulk
b) Stress
c) Strain
d) Pressure
Answer: d
Clarification: With pressure formation, the upper lip protrudes beyond the apron as a result of the development of water removal equipment, it’s no longer sufficient to use pressure forming except for tissue grades.

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Pulp and Paper Multiple Choice Questions on “Condensation Polymers”.

1. The _________ is utilized to synthesize polymers from monomers with 2 reactive functional groups by a step-wise reaction.
a) Addition polymer
b) Condensation polymer
c) Cross-linked addition
d) Addition monomer
Answer: b
Clarification: The condensation mechanism is utilized to synthesize polymers from monomers with 2 or more for crosslinked polymer reactive function groups by a step-wise reaction.

2. Every step of the reaction b/w 2 monomers produces a simple molecule, often H₂O, but sometimes NH₃ or another molecule, as a main product.
a) True
b) False
Answer: b
Clarification: These reactions are common, well known organic chemistry reactions. Each reaction step between 2 monomers produces a simple molecule, often H₂O, but sometimes NH₃ or another molecule, as a side product.

3. _________ are easily controlled synthetic polymer reactions, not like free radical reactions.
a) Precipitation reaction
b) Addition reaction
c) Radiation reaction
d) Condensation reaction
Answer: d
Clarification:The most common reactions of synthetic polymers are esterification formation of ester linkages and amidation formation of amide linkages. Condensation reactions are easily controlled reactions, unlike free radical reactions.

4. In the case of _________ it is possible to utilize a single compound to make the polymer, and that’s H₂N(CH₂)₅COOH.
a) Nylon6, 6
b) Nylon2, 2
c) Methamphetamine
d) Desoxyn
Answer: a
Clarification: In the case of nylon 6,6 (6 is the number of carbon atoms in each of the two monomers if a di-carboxylic acid and di-amine were utilized to form it) it is possible to utilize a single compound to make the polymer, and that’s H₂N(CH₂)₅COOH.

5. After a short time essentially all of the monomers will be gone and oligomers will exist in the condensation reaction.
a) True
b) False
Answer: a
Clarification: The monomers will react together initially and small polymers (oligomers) will react later. This means that after a short time essentially all of the monomers will be gone and oligomers will exist.

6. Oligomers react to form short chain polymers, then the short chained polymers react to form moderately long chain polymers. The number _________ can be predicted as a function of the extent of reaction.
a) Average DP
b) John DP
c) Pascal DP
d) Rankine DP
Answer: a
Clarification: The number average degree of polymerisation can be used to predicted the function of the extent of reaction. These oligomers will then react to form short chain polymers, then the short chained polymers will react to form moderately long chain polymers.

7. What is the name of the compound?

a) Ethylene glycol
b) Diphenyl propane
c) Hexaneamide
d) Nylon(6, 6)
Answer: b
Clarification: 1,3-Diphenyl-1,3-propanedione (dibenzoylmethane, D.B.M.) is an aromatic 1,3-diketone derivative of acetylacetone, where both methyl groups in acetylacetone have been substituted by phenyl groups. It’s a white solid which melts at 77−78 °Celcius.

8. What is the name of the compound?

HOCH₂CH₂OH

a) Ethylene glycol
b) Diphenyl propane
c) Hexaneamide
d) Nylon6, 6
Answer: a
Clarification: Ethylene glycol (I.U.P.A.C. name: ethane-1,2-diol) is an organic compound primarily used as a raw material in the manufacture of polyester fibers and fabric industry, and polyethylene terephthalate resins (P.E.T.) utilized in bottling.

9. What is the name of the compound?

-NH(CH₂)₆NH-CO(CH₂)₄CO-

a) Ethylene glycol
b) Diphenyl propane
c) Hexaneamide
d) Nylon(6, 6)
Answer: d
Clarification: Nylon 66 (also known as nylon 6-6, nylon 6/6 or nylon 6,6) is made of 2 monomers each containing 6 carbon atoms, hexamethylenediamine and adipic acid, which produces nylon 66, its name.

10. What is the name of the product?

H₂N(CH₂)₆NH₂ + HOOC-(CH₂)₄-COOH andrarr; ___________

a) Ethylene glycol
b) Diphenyl propane
c) Hexaneamide
d) Nylon6,6
Answer: d
Clarification: Nylon 66 (aka nylon 6-6, nylon 6/6 or nylon 6,6) is a type of polyamide or nylon. Nylons come in many types, and the two most common for textile and plastics industries are nylon 6 and nylon 6,6.

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Pulp and Paper Multiple Choice Questions on “Wet and Dry Strength”.

1. Wet strength additives work by forming ionic bonds between fibers.
a) True
b) False
Answer: b
Clarification: The system works by forming their own cross-linked network of covalent bonds. It is a type of bonding where pair of electrons are shared. These electron pairs are called as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms.

2. It is well known that _________ cause maximum flocculation shortly after their addition to fiber slurries.
a) Anionic polymer
b) Cationic polymer
c) Lyophobic
d) Lyophilic
Answer: b
Clarification: This was observed by Koethe and Scott in 1993.The time on the order of 10 to 100 or more minutes zeta potential decreases.

3. _________ are too large to easily be measure by their zeta potential.
a) Filbers
b) Cationic polymer
c) Lyophobic
d) Lyophilic
Answer: a
Clarification: Fibers are too large to easily measure their zeta potential. Often the assumption is made that the zeta potential behaviour of fiber fines is the same as that of the fibers.

4. What’s the name of the group?

a) Carbonate
b) Epoxy
c) Polymer
d) Starch
Answer: b
Clarification: The epoxy groups of this and other molecules that use it (such as materials utilised to prepare cationic starch) are stored in a stable form and made reactive before using them.

5. The _________ can be measured by the movement of electrophoresis.
a) Zeta resistance
b) Voltage
c) Current
d) Zeta potential
Answer: d
Clarification: The electric field cautilises movement of the water, so the measurements must be made where it is stable . A microscope must be utilised to view the particles and determine their velocity to briefly study zeta potential.

6. What is the name of the hidden part?

_________= EZ/f

a) Voltage
b) Zeta potential
c) Current
d) Factor
Answer: a
Clarification: The velocity of migration of a molecule is proportional to the electric field (E), which is the volts of the field that’s divided by the distance b/w the plates, also referred to the voltage drop per unit length, V/m and the charge of the species (Z) and is indirectly proportional to the frictional coefficient, (f).

7. What’s the name of the instrument?

a) Electrocuting
b) Electrophoresis
c) Electrolysis
d) Electro-magnetism
Answer: b
Clarification: Electrophoresis is a technique utilized in laboratories in order to separate macromolecules based on size. The technique applies a -ve charge so proteins move towards a +ve charge.

8. Colloidal _________ have a disadvantage that it’s hard to reproduce the method from operator to operator without mechanization of the system.
a) Titration
b) Sulfonication
c) Burning
d) Delignification
Answer: a
Clarification: The endpoint determination isn’t very sharp to the unaided eye. The use of a spectroscopic instrument to help determine the endpoint is crucial but adds to the complexity and cost of the method.

9. In the direct titration methods, the indicator isn’t added to the solution containing the cationic polymer.
a) True
b) False
Answer: b
Clarification: Anionic polymer is added by a burett. Initially it complexes completely with the cationic polymer.

10. Problems in zeta potential measurement occur if the H₂O has a relatively high _________strength since heating will occur, which induces convection currents.
a) ionic
b) magnetising
c) acid
d) basic
Answer: a
Clarification: Decrement the applied voltage or measurement time will be necessary. Samples must be dilute with a solution of similar inorganic electrolyte composition to observe individual particles.

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Pulp and Paper Multiple Choice Questions on “Hardwood fiber”.

1. Hardwood fibers are accompanied by vessels or vessel fragments depending on the pulping process.
a) True
b) False
Answer: a
Clarification: The major component of wood from a hardwood tree consists of libriform fibers. These are about 1 millimetre in length and about 20 micrometers in width. Wood from deciduous trees is a complicated mixture of these fibers, multi-cellular vessels (for transport of water from the roots), and other specialized cells.

2. What is the name of the portion of the tracheids?

a) Western white pine
b) Ponderosa pine
c) Sitka spruce
d) Black cotton wood
Answer: b
Clarification: Pinus ponderosa, commonly known as the ponderosa pine, bull pine, blackjack pine, or western yellow-pine, is a huge pine tree species of variable habitat native to the western United States and Canada. It’s the most widely distributed pine species in North America.

3. What is the name of the portion of the tracheids?

a) Western white pine
b) Ponderosa pine
c) Sitka spruce
d) Black cotton wood
Answer: a
Clarification: Western white pine (Pinus monticola) also known as silver pine, and California mountain pine, in the family Pinaceae, is a species of pine that occurs in the mountains of the western United States and Canada, specifically the Sierra Nevada, the Cascade Range, the Coast Range, Andgoo the northern Rocky Mountains.

4. What is the name of the portion of the tracheids?

a) Western white pine
b) Ponderosa pine
c) Sitka spruce
d) Black cotton wood
Answer: c
Clarification: Two complementary simple pits form a simple pit-pair, 2 bordered pits form a bordered pit-pair. Few pit-pairs are semi-bordered; this is pairing of simple and bordered pit. When a pit isn’t paired but solitary, it is known as a blind pit.

5. What is the name of the hardwood fiber?

a) Black cotton wood
b) Swamp tupelo
c) Eucalyptus grandis
d) Red maple
Answer: c
Clarification: Picea sitchensis, the Sitka spruce, is a hugeconiferous evergreen tree growing to near 100 meter (330 feet) tall, and with a trunk diameter at breast height that can exceed 5 meter (16 feet).

6. What is the name of the hardwood fiber?

a) Black cotton wood
b) Swamp tupelo
c) Eucalyptus grandis
d) Red maple
Answer: d
Clarification: Acer rubrum (red maple, also known as swamp, water or soft maple) is one of the most common and widespread deciduous trees of eastern and central North America. The Forest service identifies it as the most common species of tree.

7. What is the name of the hardwood fiber?

a) Black cotton wood
b) Swamp tupelo
c) Eucalyptus grandis
d) Red oak
Answer: d
Clarification: Quercus rubra, also known as red oak. It’s a native of North America, in the eastern and central United States and southeast and south-central Canada.

8. What is the name of the hardwood fiber?

a) Re maple
b) Red oak
c) Yellow birch
d) Black cottonwood
Answer: c
Clarification: Yellow Birch, also known as Golden Birch, is a huge and important lumber species of birch local to North-eastern North America. The name yellow birch indicates the color of the tree’s bark.

9. What is the name of the hardwood fiber?

a) Red maple
b) Red oak
c) Yellow birch
d) Black cottonwood
Answer: d
Clarification: Populus trichocarpa, the black cottonwood, western balsam-poplar, is adeciduous broadleaf tree species local to western North America. It is utilized for timber, and is notable as a model organism in plant biology. It’s full genome sequence was published in 2006.

10. What is the name of the hardwood fiber?

a) Red maple
b) Swamp tupelo
c) Yellow birch
d) Black cottonwood
Answer: b
Clarification: Nyssa biflora, also referred to as the swamp tupelo, or swamp black-gum is a species of tupelo that is found in wetland habitats. Swamp tupelo grows in the coastal plains from Delaware, south to southern Florida and west to eastern Texas.

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Pulp and Paper Interview Questions and Answers on “Related Pulping Methods”.

1. The Asplund process was developed about 30 years prior to TMP.
a) True
b) False
Answer: a
Clarification: The Asplund process was developed about 30 years prior to TMP.

2. Asplund process involves pre-steaming wood chips at temperature above the glass transition temperature of lignin.
a) True
b) False
Answer: a
Clarification: The Asplund process was developed about 30 years prior to TMP. It involves pre-steaming wood chips at temperature above the glass transition temperature of lignin. 550-950 kPa steam pressureat 150-170 degree Celcius.

3. What is the pressure range at which the wood chips are pre-streamed?
a) 1300-1950 kPa
b) 550-950 kPa
c) 42-78 kPa
d) 1285-1950 kPa
Answer: b
Clarification: The Asplund process was developed about 30 years prior to TMP. It involves pre-steaming wood chips at temperature above the glass transition temperature of lignin. 550-950 kPa steam pressureat 150-170 degree Celcius.

4. What is the steam pressure range at which the wood chips are pre-heated?
a) 50-200 degree celcius
b) 300-340 degree celcius
c) 1500-2000 degree celcius
d) 150-170 degree celcius
Answer: d
Clarification: The Asplund process was developed about 30 years prior to TMP. It involves pre-steaming wood chips at temperature above the glass transition temperature of lignin. 550-950 kPa steam pressure at 150-170 degree Celcius.

5. The lignin is sufficiently soft that the separation occurs at __ lamella, and fibers are left with just a hard lignin surface.
a) Upper
b) Lower
c) Middle
d) Outskirt
Answer: c
Clarification: The lignin is sufficiently soft that separation occurs at the middle lamella, and fibers are left with a hard lignin surface.

6. What is the other name of Masonite process?
a) Ignition process
b) Steam explosion
c) Mason process
d) TMP
Answer: b
Explosion: The other name of this process is called ‘steam explosion’. Chips are steamed at 180-250 degree celcius.

7. What is the temperature range at which chips are steamed in the Masonite process?
a) 1500-1690 degree Fahrenheit
b) 35-80 degree Fahrenheit
c) 155-480 degree Fahrenheit
d) 335-480 degree Fahrenheit
Answer: d
Clarification: The other name of this process is called ‘steam explosion’. Chips are steamed at 180-250 degree celcius.

8. What is the range of yield in the Masonite process?
a) 50-60%
b) 40-30%
c) 80-90%
d) 10-20%
Answer: c
Clarification: In fiberboard the fibers are held together by resins such as phenol-formaldehyde. The yield is 80-90%.

9. Chips are steamed well above the glass transition temperature of lignin, for one to two minutes until final pressure is on the order of __ MPascal.
a) 14-20
b) 4-7
c) 19-25
d) 3-4
Answer: b
Clarification: Chips are steamed well above the glass transition temperature of lignin, for one to two minutes until final pressure is on the order of 4-7 MPascal.

10. A mild explosion pulping process is being used at one mill to process __ paper.
a) Recycled
b) Un-used
c) Over-used
d) Bloated
Answer: a
Clarification: A mild explosion pulping process is being used at one mill to process recycled paper.

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Pulp and Paper Multiple Choice Questions and Answers (MCQs) on “Pulp Characterization”.

1. Pulp characterization is very important to determine the effects pulping, bleaching, refining, etc. on the properties of the pulp and, therefore, on the final paper properties.
a) True
b) False
Answer: a
Clarification: Pulp characterization is very important to determine the effects pulping, bleaching, refining, etc. on the properties of the pulp and, therefore, on the final paper properties.

2. The moisture content of pulp is calculated by drying a weighed portion of pulp in an oven at ____________ to constant weight .
a) 105 ± 3°C
b) 85 ± 3°C
c) 35 ± 3°C
d) 15 ± 3°C
Answer: a
Clarification: The moisture content of pulp’s calculated by drying a weighed portion of pulp in an oven at to 105 ± 3°C (221 ± 5T) constant weight.

3. What is the handsheet former called?
a) Dutch sheet mold
b) British sheet mold
c) French sheet mold
d) Lebanese sheet mold
Answer: b
Clarification: Round handsheets 15.9 cm (6.25 inches) in diameter are made according to T.A.P.P.I Standard T 205 and tested by methods in T.A.P.P.I Standard T 220.

4. Which of the mechanical pulps have significant fiber curling?
a) TMP
b) RPM
c) PWG
d) CMTP
Answer: a
Clarification: T.M.P. These pulps are prepared according to T.A.P.P.I Standard T 262, circulating 2% consistency stock at 90-95 °Celcius, to fully develop their strength properties by removing the curl.

5. The ____________ is a measure of the average chain length (degree of polymerization, DP) of cellulose.
a) Pulp velocity
b) Pulp viscosity
c) Lignin velocity
d) Lignin viscosity
Answer: b
Clarification: It is determined after dissolving the pulp in a suitable solvent such as cupriethylenediamine solution.

6. Increase in viscosity result from chemical pulping and bleaching operations and to a certain extent are unavoidable.
a) True
b) False
Answer: b
Clarification: Decreases in viscosity result from chemical pulping and bleaching operations and to a certain extent are unavoidable.

7. ____________ Standard T 261 is a means of measuring the fines content of pulps with a single screen classifier, the so-called Britt jar test.
a) TAPI
b) TARF
c) THNJ
d) TAPPI
Answer: d
Clarification: TAPPI Standard T 261 is a means of measuring the fines content of pulps with a single screen classifier, the so-called Brittjar test.

8. What is the name of the device?

a) Kajaani optical fiber analyser
b) Tyler optical fiber analyser
c) Kurt optical fiber analyser
d) Virgo optical fiber analyser
Answer: a
Clarification: Kajaani optical fiber classifier with analysis of 19,060 fibers (60% hardwood, 40% softwood by weight). Averages are number, 0.55 nun; length, 1.16 mm; and, mass, 1.88 mm.

9. What is the name of the device?

a) Kent pulp fiber classifier
b) Clark pulp fiber classifier
c) Max pulp fiber classifier
d) Magneto pulp fiber classifier
Answer: b
Clarification: Fiber lengths can also be determined by fiber classification using a series of at least four screens of increasingly smaller openings (TAPPI Standard T 233); two common instruments are the Clark type or Bauer-McNett type.

10. Papers containing ____________ that reduce CUSO₄ might be utilized, provided the total reducing power of the additives is known and no more than about 75% of the total reducing power of the sheet.
a) ZnS and CaSO₄
b) ZnSO₄ and CaCO₃
c) CaCO₃ and MnO₂
d) ZnS and CO₂
Answer: a
Clarification: Papers containing ZnS, CaSO₄, melamine resins, and other materials that reduce CuSO₄ might be utilized to provide the total reducing power of the additives is known and no more than about 75% of the total reducing power of the sheet.

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